Bobbin for the field-magnets of dynamos



(NdModeL) A. SCHMID.

BOBBIN FOR THE FIELD MAGNETS 0P DYNAMOS: No. 883,657. Patented May 29,1888.

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UNITED STATES PATENT OFErcE.

ALBERT SCHMID, OF ALLEGHENY, ASSIGNOE TO THE WESTINGHOUSE ELECTRICCOMPANY, OF PITTSBURG, PENNSYLVANIA.

BOBBlN FOR THE FIELD-MAGNETS OF DYNAMOS.

SPECIFICATION forming part of Letters Patent No. 383,657, dated May 29,1888.

Application filed September 1, 1887. Serial No. 248,478. (No model.)

To aZZ whom it may concern:

Be it known that I, ALBERT SoHMID, a citizen of the Republic ofSwitzerland, residing in Allegheny, in the county of Allegheny, in

. the State of Pennsylvania, have invented certain new and usefulImprovements in Field- Magnets for Electric Machines, of which thefollowing is a specification.

The invention relates to the construction of the bobbin spools for thefield-magnets of elec tric machines and to the method of securing themupon the cores of the fieldmagnets.

The object of the invention is to provide a form of spool upon which thebobbin may be wound, which may be conveniently secured upon the pole orpolar projection to which the bobbin is applied, and may be easilyremoved and replaced, and also one which will not combine with adjacentspools to divert the lines of force from the armature.

The invention will be described in detail in connection with theaccompanying drawings, in which Figure 1 is a view of a portion of afieldmagnet, and Fig. 2 is a detail of one of the spools. Fig. 3 is anenlarged end view.

Referring to the figures, A represents the fieldmagnet frame of anelectric machine, and a a represent the polar projections or poles forreceiving the bobbins. The bobbins B are wound upon spools C. Thesespools are constructed of sheet iron cylinders of the proper shape forfitting over the cores, as represented at c. The lower or outer end isprovided with a brass flange, c, which is fitted over the end of theportion 0 and fastened in any convenient manner-as, for instance, byturning out or upsetting the end of the portion 0 over the face of theflange c. The upper end of the spool is provided with a similar flange,c, fastened in a like manner, and this flange is provided with two lugs,d (2 which are designed to fit against opposite sides or ends of thecores or polar projections a of the fieldmagnet. The lugs are providedwith small holes 0 for receiving screws, by means of which they are heldin position. The wire is first wound upon the spools, and each sp'ool isheld in position independently of the others.

In constructing machines of the character to p which this invention isespecially applicable, it is usual to form the cores of ovalcrosssection, and the portion 0 of the spools is there fore made ofsimilar cross-section to fit over them. As the cores center upon thearmature, their inner ends are near each other, and were the flanges cof the spools formed of magnetic material the lines of force would tendto pass from one spool to that adjacentto it. For this reason it isdesirable that the end pieces or flanges, 0, should be of brass or someother nonmagnetic material, and likewise the lugs (1 (1 I claim as myinvention 1. The combination, with the fieldmagnet of an electricmachine, of bobbin-spools fitting over the cores or polar projections ofthe field magnet and lugs at the inner ends of the spools for securingthem in position.

2. In an electric machine, a bobbin'spool having lugs at the inner endfitting over the field-magnet core, whereby it may be secured inposition.

3. In an electric machine, aspool for receiving a bobbin of thefield-magnet, consisting of a central cylindrical portion of soft iron,an outer flange of nonmagnetic material secured to one end, and one ormore lugs secured to the opposite end for securing the spool to thefield-magnet.

In testimony whereof I have hereunto subscribed my name this 5th day ofMay, A. D. 1887.

ALBERT SCHMID.

Witnesses:

CHARLES A. TERRY, W. D. UPTEGRAFF.

